title: Systemic administration of low dosage of tetanus toxin decreases cell proliferation and neuroblast differentiation in the mouse hippocampal dentate gyrus.
abstract: IN THE PRESENT STUDY, WE INVESTIGATED THE EFFECT OF TETAUS TOXIN (TET) ON CELL PROLIFERATION AND NEUROBLAST DIFFERENTIATION USING SPECIFIC MARKERS: 5-bromo-2-deoxyuridine (BrdU) as an exogenous marker for cell proliferation, Ki-67 as an endogenous marker for cell proliferation and doublecortin (DCX) as a marker for neuroblasts in the mouse hippocampal dentate gyrus (DG) after TeT treatment. Mice were intraperitoneally administered 2.5 and 10 ng/kg TeT and sacrificed 15 days after the treatment. In both the TeT-treated groups, no neuronal death occurred in any layers of the DG using neuronal nuclei (NeuN, a neuron nuclei maker) and Fluoro-Jade B (F-J B, a high-affinity fluorescent marker for the localization of neuronal degeneration). In addition, no significant change in glial activation in both the 2.5 and 10 ng/kg TeT-treated-groups was found by GFAP (a marker for astrocytes) and Iba-1 (a marker for microglia) immunohistochemistry. However, in the 2.5 ng/kg TeT-treated-group, the mean number of BrdU, Ki-67 and DCX immunoreactive cells, respectively, were apparently decreased compared to the control group, and the mean number of each in the 10 ng/kg TeT-treated-group was much more decreased. In addition, processes of DCX-immunoreactive cells, which projected into the molecular layer, were short compared to those in the control group. In brief, our present results show that low dosage (10 ng/kg) TeT treatment apparently decreased cell proliferation and neuroblast differentiation in the mouse hippocampal DG without distinct gliosis as well as any loss of adult neurons.
authors.affiliation: Department of Integrative Traditional & Western Medicine, Medical College, Yangzhou University, Yangzhou, China.
authors.forename: Bing Chun
authors.initials: BC
authors.lastname: Yan
authors.forename: In Hye
authors.initials: IH
authors.lastname: Kim
authors.forename: Joon Ha
authors.initials: JH
authors.lastname: Park
authors.forename: Ji Hyeon
authors.initials: JH
authors.lastname: Ahn
authors.forename: Jeong-Hwi
authors.initials: JH
authors.lastname: Cho
authors.forename: Bai Hui
authors.initials: BH
authors.lastname: Chen
authors.forename: Jae-Chul
authors.initials: JC
authors.lastname: Lee
authors.forename: Jung Hoon
authors.initials: JH
authors.lastname: Choi
authors.forename: Ki-Yeon
authors.initials: KY
authors.lastname: Yoo
authors.forename: Choong Hyun
authors.initials: CH
authors.lastname: Lee
authors.forename: Jun Hwi
authors.initials: JH
authors.lastname: Cho
authors.forename: Jong-Dai
authors.initials: JD
authors.lastname: Kim
authors.forename: Moo-Ho
authors.initials: MH
authors.lastname: Won
keywords: Exotoxin; granule cell; neurogenesis; neuronal damage; sub-granular zone